Diabetes quality of life, Chemical Intolerance, and generational status in a Latino sample: an RRNeT study.

Objectives: The impact of diabetes on quality of life (QoL) includes deficits in physical functioning and emotional and mental health. Individuals with diabetes can experience significant distress related to diabetes management and burden. Comorbid conditions can contribute to QoL among individuals with diabetes. Chemical Intolerance (CI) has received minimal attention in the context of diabetes. CI is characterized by multi-systemic symptoms initiated by a one-time high dose or persistent low-dose exposure to environmental toxins. Latinos experience diabetes distress and are exposed to environmental factors at disproportionate rates. This study sought to investigate generational differences in diabetes QoL and CI in a Latino sample across generational status. Methods: To assess the modifying effect of CI between QoL and generations, the analysis was stratified by those with and without CI. Results: Compared to 2nd generation Latinos, Latino immigrants were more likely to indicate that without diabetes, their life would be better across several QoL domains. Latino immigrants had a lower A1C and BMI than2nd generation Latinos. Additionally, they were less likely to have scores indicative of CI than U.S.-born Latinos. QoL varied by generational status and suggested a greater emphasis on family and social relationships among immigrants than U.S.-born Latinos. There were no differences in health services measures across generations. Conclusions: This study highlights generational differences in the impact of diabetes on QoL. It is one of the few studies to seek to understand the impact of CI on QoL in the context of a chronic condition such as type 2 diabetes.

Chemical Intolerance and Mast Cell Activation: A Suspicious Synchronicity.

Background: Chemical Intolerance (CI) is characterized by intolerances for chemicals, foods, and drugs with multi-system symptoms. As yet, the biomechanism remains unclear. One study reported converging lines of evidence supporting a substantive association between mast cell activation syndrome (MCAS) and CI. The purpose of this study is to (1) confirm a previous report demonstrating that 60% of MCAS patients report CI and (2) examine the parallels between symptoms and intolerances in CI and MCAS. Methods: Five hundred forty-four MCAS patients were assigned a clinical MCAS score using a validated assessment instrument and were assessed for CI using the validated Quick Environmental Exposure Sensitivity Index. Results: Our outcomes confirm the previously published study where the majority of MCAS patients also have CI. There was a clear overlap between various ICD-10 diagnostic categories and CI symptoms, providing further support for a potential shared mechanism. Conclusions: Exposures to pesticides, volatile organic compounds, combustion products, and mold have previously been reported as initiators of CI. However, until recently, little was known about the biological mechanism involved that could explain the multisystem symptoms associated with CI. This paper addresses a newly identified biomechanism for disease, which may underlie a host of "medically unexplained symptoms" triggered by xenobiotics.

Does improving indoor air quality lessen symptoms associated with chemical intolerance?

AIM: To determine whether environmental house calls that improved indoor air quality (IAQ) is effective in reducing symptoms of chemical intolerance (CI). BACKGROUND: Prevalence of CI is increasing worldwide. Those affected typically report symptoms such as headaches, fatigue, 'brain fog', and gastrointestinal problems - common primary care complaints. Substantial evidence suggests that improving IAQ may be helpful in reducing symptoms associated with CI. METHODS: Primary care clinic patients were invited to participate in a series of structured environmental house calls (EHCs). To qualify, participants were assessed for CI with the Quick Environmental Exposure and Sensitivity Inventory. Those with CI volunteered to allow the EHC team to visit their homes to collect air samples for volatile organic compounds (VOCs). Initial and post-intervention IAQ sampling was analyzed by an independent lab to determine VOC levels (ng/L). The team discussed indoor air exposures, their health effects, and provided guidance for reducing exposures. FINDINGS: Homes where recommendations were followed showed the greatest improvements in IAQ. The improvements were based upon decreased airborne VOCs associated with reduced use of cleaning chemicals, personal care products, and fragrances, and reduction in the index patients' symptoms. Symptom improvement generally was not reported among those whose homes showed no VOC improvement. CONCLUSION: Improvements in both IAQ and patients' symptoms occur when families implement an action plan developed and shared with them by a trained EHC team. Indoor air problems simply are not part of most doctors' differential diagnoses, despite relatively high prevalence rates of CI in primary care clinics. Our three-question screening questionnaire - the BREESI - can help physicians identify which patients should complete the QEESI. After identifying patients with CI, the practitioner can help by counseling them regarding their home exposures to VOCs. The future of clinical medicine could include environmental house calls as standard of practice for susceptible patients.

Multiple Chemical Sensitivity in Patients Exposed to Moisture Damage at Work and in General Working-Age Population-The SAMDAW Study.

A considerable proportion of patients having respiratory tract or voice symptoms associated with workplace moisture damage (MD) could have multiple chemical sensitivity (MCS). MCS is characterized by symptoms of different organ systems in association with low-level chemical exposure. The objective of this study was to assess the prevalence of MCS among patients referred to secondary health care because of respiratory or voice symptoms associated with workplace MD compared to the general working-age population. Using three subscales of the QEESI© questionnaire, we assessed MCS in the study patients and 1500 controls in the same district randomly selected from the Finnish Population Information System. Study patients had significantly more often high scores in chemical intolerance (39% vs. 23%, p = 0.001), symptom severity (60% vs. 27%, p < 0.001), and life impact subscales (53% vs. 20%, p < 0.001). Asthma, chronic rhinosinusitis, laryngeal problems, and atopy were not associated with the presence of MCS. MCS is common among patients referred to secondary health care with respiratory tract and/or voice symptoms associated with workplace MD, and it considerably affects their everyday life. MCS should be considered as a possible explanatory factor for MD-associated symptoms.

Italian Expert Consensus on Clinical and Therapeutic Management of Multiple Chemical Sensitivity (MCS).

Multiple chemical sensitivity (MCS) is a multisystem, recurrent, environmental disorder that flares in response to different exposures (i.e., pesticides, solvents, toxic metals and molds) under the threshold limit value (TLV) calculated for age and gender in the general population. MCS is a syndrome characterized by cutaneous, allergic, gastrointestinal, rheumatological, endocrinological, cardiological and neurological signs and symptoms. We performed a systematic review of the literature to summarize the current clinical and therapeutic evidence and then oriented an eDelphi consensus. Four main research domains were identified (diagnosis, treatment, hospitalization and emergency) and discussed by 10 experts and an MCS patient. Thus, the first Italian MCS consensus had the double aim: (a) to improve MCS knowledge among healthcare workers and patients by standardizing the clinical and therapeutic management to MCS patients; and (b) to improve and shed light on MCS misconceptions not supported by evidence-based medicine (EBM).

Potential factors affecting chronic chemical intolerance associated with constitutional predisposition or lifestyle and environment during childhood: From a six-year follow-up study.

OBJECTIVE: The Japanese chemical intolerance (JCI) study was conducted in January 2012 with a cohort of 7245 adults from population-based sampling. This study aimed to investigate the childhood constitutional and environmental factors involved in the development of chronic CI from the prospective cohort study. METHODS: In the cohort, 4683 persons were identified after six years. Self-reported questionnaires were administered to the subjects to obtain information on CI status; medical history; constitution, lifestyle, and housing environment during childhood; and recent psychosomatic states. We assessed the differences between individuals with persisting CI status during the follow-up (defined as chronic CI) and controls not having CI status during the follow-up. RESULTS: A total of 2500 individuals responded. Multiple logistic regression analyses revealed significant associations between chronic CI and motion sickness to car or bus and allergic conjunctivitis during childhood. Significant associations between a possible increased risk of CI and the existence of high-voltage power lines close to housing, the use of vinyl covering in wall material, the use of strong perfume by a family member, and the experience of stinky odor of paint or wax at elementary school were observed. However, the use of carpet in floor material and plaster coating in wall material was associated with a possible decreased risk of CI. CONCLUSIONS: Some potential constitutional predisposition from childhood, including inherent susceptibility in the autonomic nervous system may be involved in the development of CI.

Validation of a Brief Screening Instrument for Chemical Intolerance in a Large U.S. National Sample.

BACKGROUND: Chemical intolerance (CI) is characterized by multisystem symptoms triggered by low levels of exposure to xenobiotics including chemicals, foods/food additives, and drugs/medications. Prior prevalence estimates vary from 8-33% worldwide. Clinicians and researchers need a brief, practical screening tool for identifying possible chemical intolerance. This large, population-based study describes the validation of a three-item screening questionnaire, the Brief Environmental Exposure and Sensitivity Inventory (BREESI), against the international reference standard used for assessing chemical intolerance, the Quick Environmental Exposure and Sensitivity Inventory (QEESI). METHODS: More than 10,000 people in the U.S. responded to the BREESI and the QEESI in a population-based survey. We calculated the overall prevalence of CI in this sample, as well as by gender, age, and income. Common statistical metrics were used to evaluate the BREESI as a screener for CI against the QEESI. RESULTS: The prevalence estimate for QEESI-defined chemical intolerance in the U.S. was 20.39% (95% CI 19.63-21.15%). The BREESI had 91.26% sensitivity (95% CI: 89.20-93.04%) and 92.89% specificity (95% CI: 91.77-93.90%). The positive likelihood ratio was 12.83 (95% CI: 11.07-14.88), and the negative likelihood ratio was 0.09 (95% CI: 0.08-0.12). Logistic regression demonstrates that the predicted probability of CI increased sharply with each increase in the number of BREESI items endorsed (Odds Ratio: 5.3, 95% CI: 4.90-5.75). CONCLUSIONS: Chemical intolerance may affect one in five people in the U.S. The BREESI is a new, practical instrument for researchers, clinicians, and epidemiologists. As a screening tool, the BREESI offers a high degree of confidence in case ascertainment. We recommend: screen with the BREESI, confirm with the QEESI.

Development and evaluation of a questionnaire instrument for chemical intolerance, based on the International Classification of Functioning, Disability and Health.

PURPOSE: The purpose was to develop a questionnaire instrument to measure difficulties in activities and participation, and impact of environmental factors in chemical intolerance, based on the International Classification of Functioning, Disability and Health, and to assess its validity and reliability. METHOD: Development in three steps: (1) choosing items of relevance for chemical intolerance with an expert group, (2) conducting interviews with persons with chemical intolerance, using sampling to redundancy, (3) conducting a survey with 112 respondents at a first assessment and 91 at a second assessment for test-retest. RESULTS: The final version of the instrument consists of 57 items divided in three parts, which showed good internal consistency in each part, Cronbach alpha: 0.73-0.87. It had good content validity, readability and face validity. Test-retest showed good to very good (≥0.61) Kappa agreement for 37 items, and moderate (0.41-0.60) for 17 items. Three items had poor or fair (<0.41) Kappa agreement. CONCLUSION: The instrument was found to be valid and reliable. It can be used as a clinical tool to help persons with chemical intolerance to receive the best suited help and support for each individual, identify key points in rehabilitation, measure rehabilitation outcome and establish priority for treatment.IMPLICATIONS FOR REHABILITATIONThe questionnaire instrument based on the International Classification of Functioning, Disability and Health which was developed and evaluated in this study, can be used to measure difficulties in activities and participation, and impact of environmental factors in chemical intolerance.Persons with chemical intolerance report lack of support from healthcare and society. Using this questionnaire instrument can help forming the best suited help and support for each individual based on his/her preconditions.This questionnaire instrument can be used to identify key points in rehabilitation and measure rehabilitation outcome.

Multiple Chemical Sensitivity.

Multiple Chemical Sensitivity (MCS), a condition also known as Chemical Sensitivity (CS), Chemical Intolerance (CI), Idiopathic Environmental Illness (IEI) and Toxicant Induced Loss of Tolerance (TILT), is an acquired multifactorial syndrome characterized by a recurrent set of debilitating symptoms. The symptoms of this controversial disorder are reported to be induced by environmental chemicals at doses far below those usually harmful to most persons. They involve a large spectrum of organ systems and typically disappear when the environmental chemicals are removed. However, no clear link has emerged among self-reported MCS symptoms and widely accepted objective measures of physiological dysfunction, and no clear dose-response relationship between exposure and symptom reactions has been observed. In addition, the underlying etiology and pathogenic processes of the disorder remain unknown and disputed, although biologic and psychologic hypotheses abound. It is currently debated whether MCS should be considered a clinical entity at all. Nevertheless, in the last few decades MCS has received considerable scientific and governmental attention in light of the many persons reporting this illness. In this review, we provide a general overview of the history, definition, demographics, prevalence, and etiologic challenges in defining and understanding MCS.

The impact of multiple chemical sensitivity on people's social and occupational functioning; a systematic review of qualitative research studies.

OBJECTIVE: Social and occupational functioning are important for psychological health. However, quantitative research has suggested that these areas can be adversely affected by multiple chemical sensitivity (MCS). This systematic review therefore sought to explore what qualitative research has suggested about how people with MCS perceive it to affect their social and occupational functioning. METHOD: Journal articles were included if they were 1) peer reviewed 2) qualitative or mixed methods 3) published in English 4) reported qualitative findings relevant to the review. Studies were excluded if they were 1) descriptive only 2) primarily concerned with environmental intolerances other than chemicals or 3) focussed on specific populations such as veterans. Quality was assessed using the National Institute for Health and Care Excellence (NICE, 2018) qualitative quality criteria. However, quality was not used to determine eligibility for inclusion. Six databases (CINAHL, Medline, PsychArticles, PsychInfo, Scopus and Web of Science) were searched between the 24th of February 2019 and 2nd of March 2019. RESULTS: Having removed duplicates, database searches identified 388 potential articles. Thirteen of these articles were eligible for inclusion. Following review, no more articles were included from the reference lists of these studies. Meta-aggregation of the findings identified seven categories. These were synthesised into three themes; 'limited access', 'loss & anxiety' and 'seeking engagement'. CONCLUSIONS: The findings suggested that MCS limits some people's social and occupational functioning. The results warrant further research, and, the development of prevention and intervention strategies. Studies predominantly recruited United States and Canadian females and had several limitations.

Mechanisms underlying nontoxic indoor air health problems: A review.

Indoor air health problems of the type non-specific building-related symptoms (NBRS; formally called "sick-building syndrome") and chemical intolerance (CI; e.g. multiple chemical sensitivity) can in severe cases lead to significant disability and poor quality of life. Apart from suffering of the afflicted individuals, the productivity loss ascribed to environmental intolerances of this kind is very costly for society. Preventive measures and appropriate treatment call for understanding of the mechanism underlying NBRS and CI. Considerable similarities between NBRS and CI suggest that the two conditions at large share mechanisms. Since typical cases of these conditions cannot be explained by toxic exposure, the present objective is to describe underlying mechanisms of psychobiological nature for which there is well-developed theoretical ground and empirical support. Focus lies on the mechanisms neurogenic inflammation and neural sensitization. Apart from describing its basic mechanisms, neurogenic inflammation is reviewed in relation to NBRS and CI regarding neurogenic switching, activation of the autonomic nervous system and axon reflex as well as interaction effects between chemical irritants, allergens, and psychosocial stressors. In addition to describing various types of sensitization, empirical support for their role in NBRS and CI is reviewed. The mechanism classical conditioning, symptom misattribution and somatosensory amplification, and nocebo are also addressed. The review rounds off with a discussion on why only a subset of individuals exposed to these indoor environments develop NBRS and CI, and a discussion on integration of the presented mechanisms, accompanied by proposed hypotheses for future research.

Chemical Intolerance Is Associated With Altered Response Bias, not Greater Sensory Sensitivity.

Chemical intolerance is a surprisingly prevalent condition or affliction characterized by adverse reactions to low levels of chemical, often odorous stimulation. Sufferers often assume that their plight is due to an uncommon sensory acuteness, yet studies repeatedly fail to reveal altered detection thresholds. Here, we investigated whether self-reported chemical intolerance is associated with altered sensory sensitivity or response bias. The sensory acuity (sensitivity; A) and sensory decision rule (criterion; B) to n-butanol was assessed using the method of constant stimuli in 82 participants with different degrees of chemical intolerance (low to high). Higher self-reported chemical intolerance was associated with a lower criterion, but not with sensitivity.

Chemical intolerance: involvement of brain function and networks after exposure to extrinsic stimuli perceived as hazardous.

BACKGROUND: Chemical intolerance (CI) is a chronic condition characterized by recurring and severe symptoms triggered by exposure to low levels of odorous or pungent substances. The etiology of CI has been a controversial subject for a long time. The aim of this review is to summarize findings on the neurological processing of sensory information during and after exposure to low levels of odorous or pungent substances in individuals with CI, focusing on the brain function and networks. METHODS: Scientific studies on CI published between 2000 and 2019 in academic peer-reviewed journals were systematically searched using medical and scientific literature databases. Only peer-reviewed articles reporting original research from experimental human studies directly associated with CI, and involving related neurological responses or brain imaging after exposure to odorous or pungent substances (i.e., in chemical provocation tests), were considered. RESULTS: Forty-seven studies were found to be eligible for a full-text review. Twenty-three studies met the selection criteria and were included in this review. Evidence indicated that differences between subjects with CI and healthy controls were observed by brain imaging during and after exposure to odorous or pungent substances. Differences in brain imaging were also observed between initial exposure and after exposure to these substances. Neurological processing of sensory information after exposure to extrinsic stimuli in the limbic system and related cortices were altered in subjects with CI. A previous documentable exposure event was likely to be involved in this alteration. CONCLUSIONS: This review documents consistent evidence for the altered neurological processing of sensory information in individuals with CI. Further neurophysiological research exploring the processing of extrinsic stimuli and cognition of sensation through the limbic system and related cortices in CI, and the appearance of symptoms in individuals with CI, are required.

Factors affecting self-reported chemical intolerance: A five-year follow-up study in Japan.

OBJECTIVE: Chemical intolerance (CI) has become a strong public health concern in industrialized countries. The Japanese Chemical Intolerance (JCI) study was conducted in January 2012 with a cohort of 7245 adults from population-based sampling as the baseline. The aim of the present study was to investigate the factors involved in the improvement and development of CI from the five-year follow-up study. METHODS: From the 7245 cohort, 735 persons with CI (case) were identified, and 1750 controls without CI were randomly selected to match gender and age for case and control groups. Self-reported questionnaires were administered to the subjects of the two groups to obtain information on status of CI; medical history; medical, lifestyle, or physical interventions; changes in living situation or occupation; and psychosomatic states. RESULTS: A total of 909 individuals responded during the follow-up period. After five years, improvement in CI was observed in 67.7% of the case group. Status of CI was reported in 6.7% of the control group. Multiple logistic regression analyses revealed that baseline atopic dermatitis and negative psychosomatic states including irritability, fatigue, anxiety, depressed mood, and somatic symptoms were significantly associated with development of CI in controls. Appropriate physical activity and maintaining a regular lifestyle including diet or sleep during the last three years of the follow-up period were significant factors for improvement of CI in the case group. CONCLUSIONS: Ensuring appropriate physical activity and regular lifestyle rather than improving physical environment lead to improvement of CI. Stable psychosomatic state is essential for preventing CI.

Chemical intolerance: involvement of brain function and networks after exposure to extrinsic stimuli perceived as hazardous

BACKGROUND@#Chemical intolerance (CI) is a chronic condition characterized by recurring and severe symptoms triggered by exposure to low levels of odorous or pungent substances. The etiology of CI has been a controversial subject for a long time. The aim of this review is to summarize findings on the neurological processing of sensory information during and after exposure to low levels of odorous or pungent substances in individuals with CI, focusing on the brain function and networks.@*METHODS@#Scientific studies on CI published between 2000 and 2019 in academic peer-reviewed journals were systematically searched using medical and scientific literature databases. Only peer-reviewed articles reporting original research from experimental human studies directly associated with CI, and involving related neurological responses or brain imaging after exposure to odorous or pungent substances (i.e., in chemical provocation tests), were considered.@*RESULTS@#Forty-seven studies were found to be eligible for a full-text review. Twenty-three studies met the selection criteria and were included in this review. Evidence indicated that differences between subjects with CI and healthy controls were observed by brain imaging during and after exposure to odorous or pungent substances. Differences in brain imaging were also observed between initial exposure and after exposure to these substances. Neurological processing of sensory information after exposure to extrinsic stimuli in the limbic system and related cortices were altered in subjects with CI. A previous documentable exposure event was likely to be involved in this alteration.@*CONCLUSIONS@#This review documents consistent evidence for the altered neurological processing of sensory information in individuals with CI. Further neurophysiological research exploring the processing of extrinsic stimuli and cognition of sensation through the limbic system and related cortices in CI, and the appearance of symptoms in individuals with CI, are required.

Multiple Chemical Sensitivity in Chemical Laboratory Workers.

BACKGROUND: Multiple Chemical Sensitivity (MCS) is an acquired disease which etiology remains unknown. It is characterized by the development of sensitivity to certain chemical products.Most of the hypotheses formulated to explain the syndrome associate it to a previous exposition to some kind of volatile chemical. University researchers in chemical laboratories suffer a phenomenon of multi-exposition to chemical agents at low concentration during long periods of time although in an irregular form. Many of these chemical agents have similar properties to those suspicious of causing MCS. This article studies the prevalence of MCS in laboratory researchers. METHODS: The study group is university researchers in chemical laboratories. The control group was obtained from administrative personnel who work in the same universities and therefore, are not exposed to chemical products from the laboratories, but have the same exposition to the rest of environmental polluting agents from the area and from the buildings of the university. In this study, it is used the Quick Environmental Exposure and Sensitivity Inventory (QEESI) (sensitivity of 92%/specificity of 95%). RESULTS: The results showed that the prevalence of MCS for the university researchers is not related to exposition by inhalation to multiple chemical agents, at low concentration. CONCLUSIONS: The results disagree with one of the main etiological hypotheses of MCS, which is based on the existence of hypersensitive people, who presents a response after prolonged expositions to very low concentrations during a long period of time.

Background factors of chemical intolerance and parent-child relationships.

BACKGROUND: Chemical intolerance is a widespread public health problem characterized by symptoms that reportedly result from low-level exposure to chemicals. Although several studies have reported factors related to chemical intolerance in adults, the impact of family members has not been reported. In the present study, we investigated the background factors related to chemical intolerance in family members and parent-child relationships. METHODS: We distributed a self-reported questionnaire to 4325 mothers who were invited to visit the Kishiwada Health Center in Kishiwada City, Osaka, between January 2006 and December 2007 for the regular health checkup of their three-and-a-half-year-old children. RESULTS: The prevalence of chemical intolerance in the 3-year-old children was almost one eighteenth of that reported by their mothers. Multiple logistic regression analyses revealed that cold sensitivity [odds ratio (OR), 1.89; 95% confidence interval (CI), 1.04-3.44], past bronchial asthma (OR, 2.84; 95% CI, 1.46-5.53), and any past allergies (OR, 2.21; 95% CI, 1.36-3.60) were significantly associated with chemical intolerance in the mother. The presence of indoor cat during childhood (OR, 1.99; 95% CI, 1.08-3.69) was significantly associated with chemical intolerance in the mother; however, the association was weak compared with cold sensitivity and past asthma and allergies. The current chemical intolerance of the mother was significantly associated with allergic rhinitis (OR, 2.32; 95% CI, 1.19-4.53), bronchial asthma (OR, 3.66; 95% CI, 2.00-6.69), and chronic bronchitis (OR, 3.69; 95% CI, 1.04-13.03) in her 3-year-old child. CONCLUSIONS: The results suggest that inherent physical constitution and childhood housing environment are associated with a risk of acquiring chemical intolerance. Children of mothers with chemical intolerance have a possible risk of respiratory hypersensitivity or inflammation. Further investigation is recommended to determine the inherent physical constitution and background environmental factors associated with the risk of acquiring chemical intolerance. The impact of having mothers with chemical intolerance on the health of children also requires further study.

Survey on changes in subjective symptoms, onset/trigger factors, allergic diseases, and chemical exposures in the past decade of Japanese patients with multiple chemical sensitivity.

BACKGROUND: Recently, with rapid changes in the Japanese lifestyle, the clinical condition of patients with multiple chemical sensitivity (MCS) may also have undergone change. Thus, we conducted a new survey for subjective symptoms, ongoing chemical exposures, the prevalence of allergic diseases, and presumed onset/trigger factors in patients with MCS and compared results with those of an old survey from ten years ago. METHODS: The new survey was conducted from 2012 to 2015 and the old survey was independently conducted from 1999 to 2003, meaning it was not a follow-up study. Patients were initially diagnosed by physicians at five medical institutions with MCS specialty outpatient services, with 111 and 103 patients participating in the new and old surveys, respectively. The controls were a general population living in Japan, with 1313 and 2382 participants in the new and old surveys, respectively. Subjective symptoms and ongoing chemical exposure were evaluated using a quick environmental exposure sensitivity inventory. Additionally, from clinical findings recorded by an attending physician, the prevalence of allergic diseases and presumed onset/trigger factors were evaluated. Differences between new and old surveys were analyzed using logistic regression analyses and significance tests. RESULTS: Compared with ten years ago: (1) Regarding factors affecting patients with ongoing chemical exposures, the proportion of patients affected decreased significantly for two items only (insecticides and second-hand smoke). The proportion of controls showing ongoing exposure to 8 out of 10 items changed significantly. (2) In patients, scores for chemical intolerances, other intolerances, and life impacts increased significantly. (3) In terms of the prevalence of allergic diseases among patients with MCS, bronchial asthma (adjusted odds ratio [AOR]: 5.19), atopic dermatitis (AOR: 3.77), allergic rhinitis (AOR: 5.34), and food allergies (AOR: 2.63) increased significantly, while hay fever (AOR: 0.38) and drug allergies (AOR: 0.40) decreased significantly. (4) With regard to construction and renovation, which was the presumed predominant onset/trigger factor for MCS 10 years ago, this decreased from 68.9% to 35.1%; in contrast, electromagnetic fields (0.0%-26.1%), perfume (0.0%-20.7%), and medical treatment (1.9%-7.2%) increased significantly, confirming the diversification of onset/trigger factors. CONCLUSION: Compared to ten years ago, for patients with MCS, an increase in avoidance behavior toward chemical substance exposures, which were presumed to be aggravating factors for symptoms, was confirmed. It has been suggested that the ongoing chemical exposure of the general population in Japan has largely changed. In addition, for patients with MCS, chemical intolerances and life impacts have become severe, the prevalence of the main allergic diseases has increased, and onset/trigger factors have become diversified.

Physical and chemical trigger factors in environmental intolerance.

BACKGROUND: Individuals with environmental intolerance (EI) react to exposure from different environmental sources at levels tolerated by most people and that are below established toxicological and hazardous thresholds. The main aim of this study was to determine the prevalence of attributing symptoms to chemical and physical sources in the environment among individuals with different forms of self-reported EI and in referents. METHODS: Cross-sectional data from a population-based study, the Västerbotten Environmental Health Study (n = 3406), were used and individuals with self-reported EI to chemicals, buildings, electromagnetic fields and sounds as well as a group with multiple EIs were identified. The Environmental-Symptom Attribution Scale was used to quantify degree to which health symptoms are attributed to 40 specific environmental exposures and sources, with subscales referring to the four types of EI. RESULTS: All EI groups, except the group with building related intolerance (BRI), reported more symptoms from the expected sources compared to the referents. In addition, individuals with chemical and sound intolerance reported symptoms from building related trigger factors, and individuals with electromagnetic hypersensitivity reported symptoms from chemical trigger factors. CONCLUSIONS: The study suggests that individuals with BRI react to fewer and more specific trigger factors than do individuals with other EIs, and that it is important to ask about different sources since three of the EI groups attribute their symptoms to a wide variety of sources in addition to the sources to which their EI implicates.